Influence of the 5'-terminal sequences on the 5'-UTR structure of HIV-1 genomic RNA.

The 5'-UTR of HIV-1 genomic RNA is known to form specific structures and has important functions. There are three 5'-terminal sequences, G1, G2 and G3, with different localizations in the cell and virion particles as well as different efficiencies in translation and reverse transcription reactions. In the present study, the structural characteristics of the joint region between the TAR and PolyA stems was analysed, and it was found that small differences in the 5'-terminus affect the conformational characteristics of the stem-loop structures. In the G1 form, the two stems form a coaxial stem, whereas in the G2 and G3 forms, the two stems are structurally independent of each other. In the case of the G1 form, the 3'-flanking nucleotides of the PolyA stem are included in the stable coaxial stem structure, which may affect the rest of the 5'-UTR structure. This result demonstrates that the local conformation of this functionally key region has an important role in the function of the 5'-UTR.

Epigenetic TET-Catalyzed Oxidative Products of 5-Methylcytosine Impede Z-DNA Formation of CG Decamers.

Methylation of cytosine has been known to play a significant role in epigenetic regulation. 5-Methylcytosine was among the first base modification that was discovered for the capability to facilitate B/Z-DNA transition as observed in CG repeated tracks. A study on gene repression by Z-DNA prone sequence as in ADAM-12 has ignited our research interest for the Z-DNA role in epigenetics. Ten eleven translocation family proteins are responsible to catalyze 5-methylcytosine to produce oxidative products including 5-hydroxymethylcytosine, 5-formylcytosine, and 5-carboxycytosine, which each may have unique function rather than the sole purpose of 5-methylcytosine clearance. Although the Z-DNA-promoting effect of 5-methylcytosine was well established, the effect of its oxidative products on Z-DNA remain unknown. In this study, the Z-DNA-promoting effect of 5-hydroxymethylcytosine, 5-formylcytosine, and 5-carboxycytosine on the CG decamer model were investigated along with known Z-DNA stabilizers, 5-methylcytosine and 8-oxoguanine. Experimental results from circular dichroism (CD) and NMR indicates that all oxidative products of 5-methylcytosine hinder B/Z-DNA transition as high salt concentration suitable to stabilize and convert unmodified CG decamer to Z-DNA conformation is insufficient to facilitate the B/Z-DNA transition of CG decamer containing 5-hydroxymethylcytosine, 5-formylcytosine, or 5-carboxycytosine. Molecular dynamic simulation and free energy calculation by MM-PBSA are in agreement with the experimental finding that 5-hydroxymethylcytosine, 5-formylcytosine, and 5-carboxycytosine destabilize Z-DNA conformation of CG decamer, in contrast to its precursor. Investigation of Z-DNA switch-on/switch-off regulated by 5-methylcytosine and its oxidative products is a further step to elucidate the potential of epigenetic regulated via Z-DNA.

5-Methylcytosine containing CG decamer as Z-DNA embedded sequence for a potential Z-DNA binding protein probe.

Attempting to elucidate biological significance of the left-handed Z-DNA is a research challenge due to Z-DNA potential role in many diseases. Discovery of Z-DNA binding proteins has ignited the interest in search for Z-DNA functions. Biosensor with Z-DNA forming probe can be useful to study the interaction between Z-DNA conformation and Z-DNA binding proteins. In this study, 5-methylcytosine (mC) containing CG decamers were characterized for their suitability to form Z-DNA and to be used in Z-DNA forming probe. The 5'-thiol oligonucleotide embedded with 5'-mCGmCGmCGmCGm CG-3' was designed and developed as a potential Z-DNA forming probe for Z-DNA binding protein screening.

S-1-containing chemotherapy for patients with non-small-cell lung cancer: A population-based observational study by the Ibaraki thoracic integrative (POSITIVE) research group.

To evaluate the efficacy and safety of S-1 monotherapy, S-1-containing combined chemotherapy and S-1 containing chemoradiotherapy for non-small cell lung cancer (NSCLC), a population-based observational study was performed. The efficacy and safety of the chemotherapies were evaluated at 13 institutes in a prefecture of Japan between April 2011 and March 2015. Datasets were obtained from 282 patients with NSCLC. For either wild-type or mutated epidermal growth factor receptor (EGFR), these three therapy groups generated almost identical response results and toxicity profiles as those in previously reported clinical trials, although the present study appeared to have slightly lower survival rates compared with those in the previous clinical trials. This may be due to the inclusion of patients in poor condition, and S-1 therapy being administered in the second, or later, line of therapy. In conclusion, the present study has confirmed that S-1-containing chemotherapy is effective against wild- and mutated-type EGFR NSCLC, and it is also tolerable in clinical practice.

Efficacy of first-line erlotinib in non-small cell lung cancer patients undergoing dose reduction and those with a low body surface area: A population-based observational study by the Ibaraki Thoracic Integrative (POSITIVE) Research Group.

The aim of the present study was to evaluate the efficacy of erlotinib, one of the epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs), in patients undergoing dose reduction and in those with a low body surface area (BSA). The association between dose reduction, low BSA and efficacy, including response rate, disease control rate, time to treatment failure and overall survival, were evaluated in patients prescribed first-line erlotinib for EGFR mutated non-small cell lung cancer patients between April 2012 and March 2015. A total of 22 patients received first-line erlotinib during the study period. A dose reduction of erlotinib for the reason of low BSA and poor performance status occurred in 14 (63.6%) of the patients: 6 (27.3%) had initial dose reduction, 6 (27.3%) had dose reduction in their clinical courses, and 2 (9.1%) had both. Dose reduction of erlotinib with the initial dose of erlotinib/BSA was >80 mg/m2, and longest-term prescribed dose of erlotinib/BSA was >50 mg/m2, which may have no association with a survival disadvantage. Dose-reduction estimation studies for TKIs may be crucial, particularly for patients with a low BSA. Future prospective studies and confirmation of these results in population-based retrospective ones investigating the incidence of dose reduction in patients with AEs and those with low BSA may be required for the efficient use of erlotinib in common clinical practice.

Neurological Symptoms of Sarcoidosis-induced Small Fiber Neuropathy Effectively Relieved with High-dose Steroid Pulse Therapy.

A 59-year-old woman was admitted to our hospital for an evaluation of a 10-day history of progressive pain and hypoesthesia of the right lower back associated with fever and constipation. Sarcoidosis was confirmed on mediastinal lymph node and skin biopsies. Although the neurological symptoms were suspected due to sarcoidosis-induced nerve dysfunction, nerve conduction studies and other routine examinations did not show any abnormalities. The intraepidermal nerve fiber density assessed on a skin biopsy was significantly reduced, suggesting small-fiber neuropathy (SFN). The patient was finally diagnosed with sarcoidosis-induced SFN, and her neurological symptoms were effectively relieved with high-dose steroid therapy.

Observational study on the efficacy and safety of erlotinib in patients with non-small cell lung cancer.

To evaluate the efficacy and safety of erlotinib for non-small cell lung cancer (NSCLC), we performed a population-based observational study. The study involved 307 patients treated with erlotinib at 14 sites (17 departments) in Ibaraki (Japan) between December 2007 and December 2010. The tumor response and disease control rates were 11.1 and 46.3% in all patients, respectively. The median time to treatment failure and survival time were 1.6 months (95% confidence interval, 41-57 days) and 5.3 months (134-181 days) in all patients, respectively. Survival was significantly prolonged in EGFR mutation-positive patients compared with negative patients. EGFR mutation-negative patients who presented with a skin rash had significantly prolonged survival compared with those without a skin rash. The most common adverse event was skin disorder, followed by diarrhea. Although 45.6% of the patients in this study received erlotinib as a fourth-line or subsequent treatment, the results from this study were similar to those of clinical studies. We deduce that erlotinib is effective against NSCLC and is tolerated in clinical practice.

Erlotinib for elderly patients with non-small-cell lung cancer: Subset analysis from a population-based observational study by the Ibaraki Thoracic Integrative (POSITIVE) Research Group.

The incidence and mortality of lung cancer have increased worldwide over the last decades, with an observed increased incidence particularly among elderly populations. It has not yet been determined whether erlotinib therapy exhibits the same efficacy and safety in elderly and younger patients with non-small-cell lung cancer (NSCLC). The aim of this retrospective subgroup analysis of data from a population-based observational study was to assess the efficacy and safety of erlotinib in an elderly (≥75 years, n=74) and a younger group of patients (<75 years, n=233) who received treatment for NSCLC. The time to treatment failure was similar in the elderly [median, 62 days; 95% confidence interval (95% CI): 44-80 days] compared with the younger group (median, 46 days; 95% CI: 35-53 days) (P=0.2475). The overall survival did not differ between the elderly and younger groups (median, 170 days; 95% CI: 142-239 days vs. median, 146 days; 95% CI: 114-185 days, respectively) (P=0.7642). The adverse events did not differ in incidence between the groups and were manageable, regardless of age. Among the NSCLC patients receiving erlotinib treatment, the outcomes of the elderly (≥75 years) and younger (<75 years) groups of patients were similar in our population-based observational study.

Bevacizumab-containing chemotherapy for non-small cell lung cancer patients: a population-based observational study by the Ibaraki thoracic integrative (POSITIVE) research group.

To evaluate the efficacy and safety of bevacizumab-containing chemotherapy for non-small cell lung cancer (NSCLC), we performed a population-based observational study. The efficacy and safety of bevacizumab-containing chemotherapy for NSCLC patients were evaluated at 14 sites (17 hospital departments) in a prefecture of Japan between December 2009 and August 2011. Complete data sets were obtained from 159 patients with NSCLC. The median age was 66 years, and 34.0 % of the patients were 70 years or older. The overall response rate to bevacizumab therapy was 41.6 %, and the disease control rate was 78.5 %. In 88 patients who received bevacizumab-containing chemotherapy as first-line therapy, the response and disease control rates were 55.0 and 78.9 %, respectively. The incidence of clinically significant (grade 3 or more) adverse events was generally low: proteinuria occurred in 2 (1.3 %) patients, hypertension in 2 (1.3 %), hemoptysis in 1 (0.6 %), and interstitial pneumonia in 1 (0.6 %). The time to treatment failure (TTF) in the 159 patients was 169 days, and the median overall survival (OS) was 580 days. In patients who received bevacizumab-containing chemotherapy as first-line therapy, the TTF and OS were 152 and 520 days, respectively. The difference in TTF between patients who received bevacizumab-containing chemotherapy as first-line therapy and those who received it as second-line or later-line therapy was not significant (p = 0.4971). With regard to first-line therapy, the difference in TTF between patients treated with carboplatin + pemetrexed + bevacizumab and those treated with carboplatin + paclitaxel + bevacizumab was not significant (p = 0.9435). We deduced that bevacizumab-containing chemotherapy is effective against NSCLC and also tolerable in clinical practice.

[S-1 activity in non-small cell lung cancer in clinical practice].

OBJECTIVE: We evaluated retrospectively single-agent S-1 chemotherapy in non-small cell lung cancer patients in clinical practice. METHODS: Sixteen consecutive patients treated with single-agent S-1 for NSCLC between July 2005 and June 2007 at the Department of Thoracic Surgery, Tsuchiura Kyodo General Hospital. The treatment schedule comprised oral administration of S-1 at 80-120 mg/day. One cycle of S-1 consisted of consecutive administration to 14 (10 cases)or 28(6 cases)days followed by a 14-day rest. RESULTS: Patients profiles were: M/F: 11/5, median age 68 years old(range 51-83), PS 0/1/2/3: 2/6/5/3, adeno/squamous/large: 13/2/1, clinical stage 3A/3B/4: 3/4/9, prior chemotherapy regimens 0/1/2/3/4: 2/3/4/5/2, prior surgery/radiation: 12/5 were performed. Median number of delivered cycles was 5 cycles(range 1-13). Grade 3 hematological toxicities were anemia(6%)and thrombocytopenia(6%). Grade 3 non-hematological toxicities were nausea(6%)and vomiting(6%). Response of 13 patients could be evaluated after 2-4 cycles of S-1. Four partial responses were observed, for a response rate of 31%. The survival time was 67-852 days(average 14.0 months), 1-year survival rate was 74.0%, median time to progression was 4.6 m, and 1- year progression free survival was 25.0%. CONCLUSION: Single-agent S-1 chemotherapy has modest activity and is the one of the important regimens and tolerable for elderly, poor-PS, recurrent patients with NSCLC in clinical practice.

A population-based study of gefitinib in patients with non-small cell lung cancer.

Survival data for non-small cell lung cancer is typically reported from clinical trials that include patients fit enough to meet treatment criteria. The denominator of all patients from which the gefitinib-treated population is derived has rarely been reported and the impact of gefitinib on population-based outcomes is difficult to measure. We have retrospectively reviewed data of 626 patients who received gefitinib in Ibaraki Prefecture (with a population of 3 million) in Japan from July 2002 until September 2007. Overall response rate was found to 30.8%, and the median survival time was 8.0 months (95% confidence interval: 7.0-9.0 months). Female gender, good PS, and adenocarcinoma were significantly associated with prolonged survival. Adverse events were generally mild and were mostly skin reactions and diarrhea. Our population-based study has generated similar results to those previously reported in published clinical trials, which had restrictive criteria for eligible patients.